Content transmitted by a digital information device is various digital data. The data is, for example, moving image data such as MPEG2 and MPEG4, audio data, stream data, text data, or still image data. Since such digital data can be essentially duplicated without being deteriorated, it is necessary to pay special attention to the copyright of the content. Various proposals are made to increase the convenience of the content while protecting the copyright of the content (see Non Patent Literatures 1 to 3, for example).
[Non Patent Literature 1] DTCP Specification Volume 1 Revision 1.51, http://www.dtcp.com/data/info%2020071001%20DTCP%20V1%201 p51.pdf
[Non Patent Literature 2] DTCP Volume 1 Supplement E Mapping DTCP to IP, Revision 1.2, http://www.dtcp.com/data/info%2020070615%20DTCP%20V1SE%2 01p2.pdf
[Non Patent Literature 3] ARIB TR-B14, Terrestrial Digital Television Broadcasting Application Rule Technical Material, Association of Radio Industries and Businesses
Each of the above Non Patent Literatures 1 to 3 does not assume the possibility that new copy control information is added in the future, and does not consider the case where content is transmitted to both of a device capable of interpreting the new copy control information and a device incapable of interpreting the new copy control information.
The present invention has been made to provide an information processing apparatus capable of protecting the copyright of content while effectively using the content, even when new copy control information is added in the future.
In order to solve the above problem, according to an aspect of the present invention, there is provided an information processing apparatus comprising:
an authentication and key exchange processing unit to perform an authentication and key exchange process with a communication device;
a packet selector to determine whether a packet transmitted from the communication device is a content packet comprising encrypted content or a CCI packet comprising at least one CCI set corresponding to a combination of at least one piece of copy control information and a CCI set identifier for identifying each CCI set;
a content key generator to retrieve a content key based on an authentication key generated in the authentication and key exchange process, and the copy control information included in the CCI packet;
a content decryption unit to decrypt, based on the content key, the encrypted content which is included in the content packet and received following the CCI packet;
a CCI set identifier management unit to manage a CCI identifier corresponding to recognizable copy control information;
a CCI selector to select, when the packet determined by the packet selector is the CCI packet, a CCI identifier to be used in a receiving process by judging whether or not the CCI identifier included in the CCI packet corresponds to the CCI identifier managed by the CCI set identifier management unit;
a CCI analyzer to analyze copy control information corresponding to the CCI identifier selected by the CCI selector;
a content processing unit to perform, based on an analysis result of the CCI analyzer, the receiving process on the content data corresponding to the content packet received following the CCI packet;
a first communication connection unit to perform the authentication and key exchange process; and
a second communication connection unit to transmit the content packet and the CCI packet.
Further, according to another aspect of the present invention, there is provided an information processing apparatus comprising:
an authentication and key exchange processing unit to perform an authentication and key exchange process with a communication device;
a CCI packetizer to generate, when receiving a content request from the communication device with which the authentication and key exchange process has been successfully performed, a CCI packet of corresponding content data, the CCI packet comprising at least one CCI set corresponding to a combination of at least one piece of copy control information and a CCI set identifier for identifying each CCI set;
a content key generator to retrieve a content key for encrypting the content data based on an authentication key generated in the authentication and key exchange process, and the copy control information included in the CCI packet;
a content packet generator to generate a content packet comprising label information corresponding to the authentication key and encrypted content obtained by encrypting the content data using the content key; and
a data output unit to transmit, after transmitting the CCI packet, the content packet to which the copy control information included in the CCI packet is applied.
According to the present invention, it is possible to protect the copyright of content while effectively using the content, even when new copy control information is added in the future. [BRIEF DESCRIPTION OF DRAWINGS]